1. Field of the Invention
The present invention relates to an image forming apparatus provided with an image reading apparatus and a document feeding apparatus which are stacked on an apparatus main body.
2. Description of the Related Art
Conventionally, there is known an image forming apparatus comprising: an apparatus main body which includes an image forming portion configured to form an image on a sheet; an image reading apparatus provided on an upper portion of the apparatus main body; and a document feeding apparatus provided on the image reading apparatus so as to be openable and closable through a hinge mechanism, and configured to feed a document to the image reading apparatus. The image reading apparatus is configured to read the document which is automatically fed by the document feeding apparatus, and transmit information on an image of the document to the image forming portion. The image forming portion is configured to form the image of the document on the sheet based on the information on the image which is transmitted from the image reading apparatus.
FIGS. 11, 12, and 13 are views illustrating a conventional hinge mechanism 1. An image reading apparatus 2 is mounted to a frame 3a serving as a skeletal structure of an apparatus main body 3. A hinge base 4 is fixed to a back portion 2a of the image reading apparatus 2 with screws 5a and 5b. One hinge piece 6a of a hinge 6 is fixed to an upper part of the hinge base 4. A document feeding apparatus 7 is fixed to another hinge piece 6b of the hinge 6.
In the hinge mechanism 1, however, when the document feeding apparatus 7 is pivoted about the hinge 6 and opened with respect to the image reading apparatus 2, a load of the document feeding apparatus 7 is applied in a concentrated manner to the back portion 2a of the hinge reading apparatus 2 to which the hinge 6 is fixed. Therefore, the image reading apparatus 2 needs to have a rigid structure.
In view of the above, Japanese Patent Application Laid-Open No. 2003-51906 discloses an image forming apparatus configured to reduce the load to be applied to the back portion of the image reading apparatus.
However, the image forming apparatus disclosed in Japanese Patent Application Laid-Open No. 2003-51906 has the following problem to be solved. That is, a moment in a front-back direction of the image reading apparatus, which is generated due to a self-weight of the document feeding apparatus, is applied to the reader in some degree, and hence the structure of the reader needs to be set more rigid to a degree corresponding to the moment to be applied.